Coffee each day keeps the doctor away?

What helps you peel yourself out of bed in the morning? …Gets you through that afternoon meeting? …Helps prevent you from falling asleep on your textbook while studying for midterms? …All of the above?

If the answer is coffee, you are not alone. Most people consume the beverage for the caffeine content and jolt of energy and alertness, however, there may be beneficial health effects for long-term addicts, some effects are even shown in decaf drinkers.

Image courtesy of Paul/FreeDigitalPhotos.net

Coffee used to be linked with negative health outcomes. It has since been discovered that coffee drinkers are often also smokers, and smoking habits contribute more often to death and disease, rather than long-term coffee drinking. Your daily cup of joe actually contains protective factors which may reduce your risk of type 2 diabetes, certain types of cancer and depression.

The largest prospective cohort study to date, published in the New England Journal of Medicine, followed 229,119 men and 173,141 women over a period of 14 years to evaluate lifestyle factors and health. Results indicated that when adjusting for smokers, there is an inverse relationship between drinking six or more cups of coffee a day and a reduction in risk of all causes of death, except for cancer (10% decreased risk for men; 15% decreased risk for women). Results were similar for both regular and decaf coffee drinkers.

Since many individuals enjoy coffee (but maybe not six cups a day), additional studies indicate possible disease-specific benefits even when consuming less.

Coffee and Type 2 Diabetes A meta-analysis from the journal Nutrition Reviews found that consumption of four or more cups a day resulted in 35% reduction in risk of Type 2 Diabetes. A second meta-analysis in the same article found a 7% reduction in risk with each cup of coffee consumed during the day. Results were also present in those who drank 3-4 cups of decaf.

Coffee and Colorectal Cancer Although the above study published in the New England Journal of Medicine did not find a reduction in risk of cancer, other studies indicate different results. For example, an article published in Food and Function indicates that heavy coffee drinkers (6 cups or more a day) benefit most from non-digestible material in coffee reducing the risk of colorectal cancer. Though, moderate drinkers also show some benefit due to the dietary fiber content. The article states that the larger the serving, the better for helping escort carcinogenic and other toxic materials out of the body.

Coffee and Depression In a 10-year prospective cohort study of 50,739 women published in the Archives of Internal Medicine, results showed that about 4 cups of caffeinated coffee (550mg or more) a day reduced the risk of becoming depressed. Results were not significant for decaf coffee drinkers or for those who consumed other caffeinated beverages like soda or tea.

Image courtesy of pixbox77/FreeDigitalPhotos.net

What are some of these “magical” compounds associated protective effects?

Bioactive Molecules — dietary fiber and minerals. Similar to properties found in fruits and vegetables.

Antioxidants — including phenolic compounds (may play a role in weight control and shown to reduce body fat accumulation) and melanoidin (acts like dietary fiber). Similar to antioxidants found in green tea, red wine and chocolate.

It is critical to mention that this list of health effects and compounds found in coffee are not exhaustive of the present findings. And individuals have varying levels of tolerance which must be taken into consideration. Although a lot of progress has been made on the benefits and risks of long-term coffee drinking, the associations between coffee and health benefits are by no means causational. Much more research must be done.

Increasing or beginning consumption of coffee is not recommended due of the above findings. However, for those current and chronic coffee consumers, drink up–but ditch or go light on the cream and sugar.

[Due to present studies being conducted mostly on health professionals, the results may be biased due to the “healthy worker effect”.]

Thank you for reading! I would not advise drinking coffee just for the fiber contents, but the compounds in it have been correlated with aiding in excretion of waste, especially when consuming in higher doses. Unfortunately, the articles did not include the food questionnaire results, but this is a good point that you bring up.

Wow–these stats are mind blowing! Normally I consume only 1 or 2 cups of coffee a day for fear that any more is not healthy…Every once in awhile there are days when a 3rd cup may be in order…I will no longer deprive myself of a 3rd or 4th cup should I need it ☺ Hold the sugar of course….

Search MTSG posts

About Mind The Science Gap

Mind The Science Gap was a Science Communication Training blog that ran between 2012 - 2013.

Each semester, ten Master of Public Health students from the University of Michigan participated in a course on Communicating Science through Social Media. Each student on the course was required to post weekly articles here as they learned how to translate complex science into something a broad audience can understand and appreciate. And in doing so they were evaluated in the most brutal way possible - by the audience they were writing for!